Extensible suspension for drawers and the like



J. R. CLARK May 15, 1945.

EXTENSIBLE SUSPENSIONS FOR DRAWERS AND THE LIKE 5 Sheets-Sheet l Filed Aug. 15. 1 941 7mvEyToR. Jaynes y(fn (5 ATTORNEY.

J. R. CLARK 2,376,121

EXTENSIBLE SUSPENSIONS FOR DRAWERS AND THE LIKE May 15, 1945'.

Filed Aug. l5, 1941 5 Sheets-Sheet 2 INV ENTOR.

l ATTORNEY.

May 15, 1945# J.' R. CLARK 2,376,121

EXTENSIBLE SUSPENS:[NSl FOR DRAWERS AND THE LIKE Filed Aug. l5, 1941 u IMYENTVOR. f mail@ Mrk d ATTORNEY.

May 15, 1945. 2,376,12

` EXTENSIBLE sUsPENsIoNs FOR DRAwERs AND THE LIKE J. R. CLARK Filed Aug. 15, 1941 5 sheets-sheet 4 May 15, 1945. y J, R CLARK 2,376,121

EXTENSIBLE SUSPENSIONS FOR DRAWERS IANDTHE LIKE 0 .sa 4a Jo 6o 70 au w /00 WEATTORNEY.

Patented May 15, 1945 OFFICE EXTENSIBLE SUSPENSION FOR DRAWERS AND THE LIKE.

James R'. Clark, Rochester N. yY., assignor to Yawman & Erbe Mfg. Co., Rochester, N. Y., a cor- I poration of New York.

`Application August l15, 1941, serial No. 407,035

3 Claims.

- This invention relates tohextensiblesupportsand more particularlyto` an. improved construction in extensible suspensions for drawers yand thelike. f'\ o. v

In suspensions of this character, itis essential that the bearings thereoffhave the smallest possible frictional resistance, that the bearings cause a minimum amount of noise during operation, and that the bearings lpermit thefmaximum extension or openingof the drawer. r In addition,

the construction ofthe suspensionl should be l such that instead of applying high` stresses, t bearings in motion, -these stresses shouldV be applied to bearings' inja stationary condition thereby greatly reducinglthe roller bearingv Wear and also, reducing the roller wear on their supe porting tracks. f

The mainl feature o f the `present inventionv relates to an extensible suspension which is relatively simple and inexpensive .and yet satises the exacting requirements just specified.

Other features and advantages will appear from the detailed description and claims when taken with the drawings in which:

Fig. 1 isa vertical longitudinal section of a fragment of a ling cabinet showing the suspension of the present invention in its closed posi- 'A y i i Fig. 2jis a transverse section taken substantiallyon the line 2-2 `(Fig. 1) showing therelation of vthe case of the cabinet with its case strip, as well as the slide and the drawer, together with f the 'several bearings on which the drawer and the slide are mounted for movement out of and intc' the case; v

. Fig. 3 is a view similar to thaty oi Fig. 1, showing how the drawer moves as a unit with the slide in its extreme outer position;

Fig. 4 is a View similar to that of Fig. 3 except that it illustrates the extreme outer position of the drawer to which position it has been moved independently of the slide, from the position shown in Fig. 3; Fig. 4a is a viewof a detail of Fig. 4;

Fig. 5 is a side View of a case strip particularly illustrating the mounting of one-pairof rollers on the lower track thereof and also showing the separator for these rollers and the arrangement' for retaining the separatorl andthe rollers in vertical position; n

Fig. 61s an enlarged section taken on the line 6-)6 of Fig. 5 illustrating various detailsvof the case strip and of certain parts mounted thereon as also shown in Fig. 5; l

n Fig. 7 is a plan View.; and Fig. aside eleva- 55 tion of` the slide on which the drawer is movably mounted;

Fig. 9 is a vertical-section on the line 9-9 of Fig. 7 showing the construction of the inner surface of the side pieces of the slide as Well as the mechanism mounted on this side piece;

Fig. 10 is a transverse section on the'line 10A- I0 of Fig. 9 showing particularly the mounting oi the roller bearing on the lower track of the sid piece; and 4 1 Figs. l1 and l2 are side views of a modiied form of the invention in which Fig. 11 shows the Vslide in itsextreme outer position with the drawer telescoped therein while Fig. 12 illustrates the slide and `drawer each in its extreme extended position;

Figs. 13 and 14 are enlarged detail views respectively of thelstop on the case strip and the stop on the drawer strip illustrated in Figs. 11 and 12,; and

Figs. 15,- 16, 17 and 18 are charts-useful in describing the invention.

Referring to the drawings, the numeral 5 designates a rectangular metal case which may be a p art of a filing cabinet. This case'is closed at its top, bottom, sides and back but has one or more drawer openings at the front thereof. The side walls of the case have opposed pairs of horizontal case strips 6 attached thereto in any suitable manner. The case strips are channel-shaped with the free edges of their horizontalanges facing each other to Aafford an upper internal track 6a. and a-lower internaljtrack 6b. These tracks cooperate with suitable rollers enabling the rectangular slide l (Fig. 7) to be telescoped into the cabinet while the slide telescopically receives a drawer 8.

Y The lower track 6b of each case strip supports the rollers 9 and I0 which are rotatively irnounte'd on horizontal pins Il at'the ends of a separator strip I2, serving to maintain these rolledge of the separatorI strip, thus preventing it.

from tipping over. It will be appreciated that Vthe rollers 9 and l0 need not be of the ball-bear'- ving type but may follow the simplest construction since the only load carried A on the pins H is vthe light weight of the separator I2the working load on these rollers being carried solely at their peripheries. l The slide l, which is of' generally rectangular frame construction, has a width such that its sides are received within the case strips B. The slide comprises two opposed parallel side pieces I4 and end strips I'I and I8. Each side piece I4 is generally channel-shaped (Fig. its horizontal flanges 14a and I4b respectively providing an upper internal track and a lower track, having an internal and an external track surface. Each ilange |419 has attached thereto a downwardly projecting portion I4c in turn provided with a horizontal flange I4d. It will be noted that the flange I4b and the vertical ;portion rjI4c define with the case strip 6 a recess in which thezsupporting rollers 9 and I0 travel .(Fig. 2). .The front ends of the side pieceslf4are `joined'together by a horizontal strip 'II secured to the l flange portions Md, being welded or otherwise erator pulls on the drawer handle H. The frictionsprings-i34 on the slide 'I (see especially Figs.

,. (hand 9) engage the side of the drawer at this `timeso r`that the drawer 8 and the slide movev toattached to these parts, whilethe-reanendsof i the side pieces I4 are joined by a Verticallyfextending strip I8 similarly secured thereto. The central part :of `the slide is transversely reinforced by a horizontal strip I9 secured to the `flanges Md in thesamemanner -as the front Strip-I1. Ilhe intermediate -portion `of the strip` IS-is `oflset -downwardly `and has rubber stops 20 secured thereat whichzen'gage the cross rail2| lof the case (Fig. 3), to limit the normal outward movement Vofthe slide. Itnwill be appreciated, however,thatfwhen the drawer 8 has been removed from the slide, the front end of theslide -can be-elevated to disengage the bumpers'ZIl from the crossfrail 2I sof-that theslide can also-be removed" froml the case. l.The upper -rear Acorner `oi eachof the frame strips'l 4 carries a ball-bearingx-nounted` rol-lerf22/ or 1alternatively al pinmounted I roller. This roller engages the under sideof the relatedtrackportion--Ea-of the casestripin the courseofrthe withdrawal of the slide from'the case las-will be lhereinafter described. The mentioned flanges I4b of the slide engage therollers Sand-I 0, as best shown in Fig; 2.

The internal surface `of the flange I4b of the slide,serves as a track'fortheV spaced rollers 24 `and 25l (-Fig.-9). These Arollers are mounted on pivot pins'2-3 atthe respective ends ofA a separator stri'p26, the 'intermediate' portion of which is ofreduCed'Width, leaving front-and rear vertical -extensions 21 and 21a. OnI the rearextension 21a, there-is-mounted a roller 28 pivoted directly -above'the roller VV25 in such aposition that 4it=engages the' internal surface of the track I4a.

vTherollers v25 and 28"are spaced vertically, `just sufficient to receive freely therebetween, `a horizontal flange 4| carried on the adjacent side of the tdrawer. The intermediate reduced -portion i ofthe Aseparator '25 for theY rollers '24 and 25, is engaged by a pair of spaced ears 3| struck out ofitsside piece I4 to'hold the separator `vwith' its relatedrollers'in upright position and to limitthe lengthwise travel thereof.

Each side piece I4 of the slide is provided near the rear--endthereofwith a leaf-spring 34, The frontend `of-this springV is welded or otherwise attached tothe slide-strip at 35, while'the other end of'the Aspring extends rearwardly adjacent the ball-'bearingroller 22. It will be understood that the leaf springs 34 frictionally engage the drawer '8 and 'thus tend to hold the drawer and slide I `together Awhile `the slide is being withdrawn to its extended'position. After reaching this kposition, a slight additional pull disengages the drawer from the leaf springs 34 so that the drawer can be extended further, independently of the slide. Each slide strip I4 has attached thereto a V-shaped piece -'36 'with' the apex' thereof gether asa unitto the position shown in Fig. 3 wherethe bumperl engages the cross rail 2| to limit the outward movement of the slide. During this outward-movement of the drawer and the-.,sli-de, the slide rolls on the pairs of spaced rollers 9 and I0 at the opposite sides of the case, thesek rollersl :also having translatory y movement with respectvtotthe slide Lat this' time. `When,

intthescourse-.of thismovement the ycenter ofA gravity of the slide and of the drawer iswoutside ofthe rollers 9 and I0,`the-ballbearing rollers 22 'engagel they upperttracksiI `15a i to s support' the slide inf horizontal. position.

It'willbe..appneciated since these rollers-.Sand L0 roll bon l'fthe track lBb and #also onA the under surface :of the .track l 4b of` thegslide, that there is relatively kno fwear :on-the pins I'I ,f which pins aremounted onf-the -separator' strip: I2. This type of roller-.in addition tobeing theleast expensive ofV-all rollingibearings isalso themost quiet in operation. illlhougna ballebearing'type of roller 22` has-:been` providedv-atfeachof the rear corners of the slide, this roller bearing is fverylightly stressed, Awhile it iris ,in-motion; namely, dur-ing thetimethat itaistraveling fromthe point A where it-'iirst engagesthe track `6a` of 'the side strip to -a-pointTB-where-it comestorest in the position-shown in Fig.r 3. -(Seegraph V,-Fig. 5.) Incidentally, the ball-bearing roller -22 may be replaced by a lsimple 1 pin Itype roller such as shown LAatlSV andf-Il Asthe operator continues to pullf-onthe handle H-after the bumper 20. has engagedI the cross rail' 2 I the ldr-awer moves with respect to the slide on the rollers 24 and 25 'resting onrthef track I-4b landsupporting the flange 4 I-'onzthe drawer. 0f course;as thel drawer moves `toa poi-nt where-its cen-ter of gravity is outside @dwellers-24, the roller 28,'-at -each -side of the `drawer,w-illaengager the Idrawer strip -4-I and 'the track-l4afof the side piecefthus supporting the drawer in its outer horizontal position as During the clo'singofi *theA drawer,` the 'drawer is first telescoped intoy the-slide-*'I, the slide being held inthe pos'ition'of zFigsj and 4s bythe spring 'unit-'into their -o'losed position lwithin Ithe case.

" In the'modified `'forni of the invention v"disclosed .infigs 1li -to-l4 inclusive the springs 34, 34and S, Si have been replacedr by an l1embossed-fportion 42 in each flange 6a of the case-stript`5 (Fig.' 13) vand byal similarl embossed portion43 in thefiange 4I of .each Adrawer strip'i40 (Fig. 14'). "'.I'heembossed portions ""42 cooperate .with the. rollers `2 2 on the slide while the embossedportions'43 co operate with rollers 24.v "Thus, the portions 42 engage thelrollers 22.on the slide when` the slideV amountV of Wear onthe bearings 22 will 'be is in its Ifully Vextended position (Figs. `11"and 12) during the .opening of the drawer. ever,\the drawer is moved into the case, the resistance, arising from the engagement between rollers 22 and portions 42, holds the slide stationary until the drawer has come against the slide thereby dislodging these rollers fromthe mentioned portions 42. lThis arrangement serves the same purpose as the springsA S, S (Fig. 4a). Similarly, the embossed portions 43 inthe flanges 4I of the drawer strip 4l), -engagethe rollers 24 when the draweris fully' telescoped in theslide (Fig. ,11).I Thus, as the drawer 'in 'its jclosed position (similar to Fig; 1), is Withdrawn from the case 5, the resistance of the rollers 24k in the embossed portions 43 holds theslide fand drawer together so' that they move-as a unituntil the stop 2D engages the cros rail 2l'. v.At this point further withdrawal of the drawer disengages the rollers 24 from the embossed portions 43 allowing the drawer to open to its full extent. This action duplicates the function of the previously described spring 34. Y l

Inlorder to appreciate the load ycharacteristics on the bearings of different types of drawer slides in different positions of the drawer as it is with. drawn from the` case, the graphs' of Figs. 15 to 18 inclusive are provided. `In these-graphs there are given the bearing pressures `with relationto the total weight of the loaded drawer, disregarding'the weight of the slide itself. It should be remembered that' the total drawer 1o'ad is divided equally between the two sides of the drawer slide. If the actualweight of? a loaded drawer, for example 80 pounds,.is multiplied bythe respective percentages shown in the graphs, the resultingy products will give the.pressures at the respective bearing-points. 1 In thegraphs of` Figs. 15 to 18 the `respective drawer openings are shown in ,l termsof Apercentage of total drawerV opening and the total drawer opening is based on the drawer suspension of the present invention, takenasone hundred percent. To simplify the graphs, the

When, hownegligible in comparison with other situations illustrated in the graphs of Figs. 16 vand 18. v In graph W (Fig. 16), it is assumed that the friction springs 34, or stops 42, have notbeen drawn to its limiting positionin the slide before the slide is picked up by the drawer and in turn withdrawn from the case to the full opening of the drawer. Also, in graph W, Arepresents the point at which the center of gravity of the drawer advances beyond'the forward case roller l0 so that the pressure. begins to take place at the bearing roller 22. B isk the point at which the drawer picks up.the slide and starts the slide moving out of the case. It will be remembered from curve V `that in accordance with. the present invention,.the slide stops its motion at the point B. The positions ofA these pointsare not the same as in graph V, because the slide 1 rst pulls out of the case in graph V, but remains first in the case in graph W, changing the distance relationships. However, in the graph W, the pressure line B--C is shown in full line since the bearing 22 must now rotate against the track 6a, during which wearwill take place. The prop ortionate amountof wear is shown by the shaded area beneaththis-line and should be contrasted with the shaded area under the curve V. This demonstrates the great advantage from the standpoint of wear in the present construction center of'gravity is also taken as-a fixed point 45 slightly less than half way from front to rear of drawer 8, as is Vindicated by the vertically extending arrow of Fig. 4. f I i In Fig. 15v the graph Vrshowsthe load on the ball-bearing 22 of which one such bearing is located at each rear corner of the slidev and in which the friction springs 34 cause the slide I to withdraw with the'drawer as far as it will go as described above. At the point A in this graph the center of gravity of the drawer has advanced to a point where the pressure of this rear bearing 22 starts to be applied against the upper ange 6a. of the case strip, as the slide l together with the drawer 8l are withdrawn as a single unit. At the point B,the slidecomes to rest .since the bumper the safe stress of the bearing parts. Thus, the

shaded area under the portion A--B of the curve yV represents the pressure and distance relation which measures the wearing effect on the bearing parts. From this graph, it will be realized that by using the friction springs 34 to cause the slide and the drawer to move as a unit, the

over the arrangement permitting the drawer to be Withdrawn iirst and subsequently permitting the slide to be withdrawn. Graphs X and Y (Fig. 1,7)r showv the"comparison between thev most severely stressed rollers, which were found to bethe front roller l l); in the situations paralleled loycurves V and W respectively. These rollers are of the type that do not in themselves wear appreciably, but the wearing effort will take effect on the wear track only, that is, the case strip and the drawer strip. Therefore, this p air of curves is useful in showingthe advantage of the proposed frictional retaining springs 34 in reducing wear on the parts contacting the rollers I0. It should be remembered that the graph DG shown as in dotted line in its high range is a stationary contact between the slide pressure applied to an upper center bearing of a.

conventional progressive slide which bearing is the most severely stressed both in itself and in its wearing eii'ect on its track. The type of bearing is the same ball or pin design as at 22 of the present arrangement. From this graph it will be seen that this type of suspension provides a reduced opening of the drawer and the bearing thereof is the most severely stressed of those under consideration. In this graph, A is the point where the drawer load is transferred to the upper center bearing, while B is the limit of the drawer and slide travel which limit permits only 96 per cent drawer opening as compared with that of the present invention. Since, in this graph, the load curve A-B represents the load on a moving bearing, it 'is shown in full line. The shaded area.

under; this indicates-1 relative; wearing actione Since-ai ballibearing: similar' td 22: is customarily-v used inw conyentionai;` type ofi slide and;y encounters! moderate wear, .the comparison; between graphsf V.v andi W'f' shows4 that tliez-wearr factor:- is, negligible.` with thist type.- of bearing: 22 in thef present invention.

Eromithe: foregoing; it willabe uri'derstood:l that. thel present:v invention proifides-4 a'; draweresuspen sion: oi simplelconstruction which; reduces; toJ a. frictional resistance; asa-Well. asit noise and;wear.

Whatllclaim is:V

1; In adrawer;suspension"construction, ae' case having: side walls g a pair'of;channelishaped` strips mounted'l onzsaid walls.; with', the channelsz of saidr` stripseiacingeach: other, each oisaid stripsrpro.- vidin'gsanupper and aulower internal track; a slide including channel-shaped' side pieces each providedwithan-internal upper track aswell aswithf aninternal lowerf track and with an eX-ternaflfl lower track, each side piece-nesting withiniaside strip, a roller rotatably mountedon the rear por tion of each side pieceto engage thel-upper'intermal-track of its. related strip, aset off spaced* rollers rollingfon' the lower track of eachicliannel' strip andon the external lower'trackof arelated side 'f piece to alord inward and4 outward* travel of` saidslide means for'limitingfthe outward`move ment of^ the slide, a drawer of a sizerto lie-received within said slide, a second set of.' spaced rollers rolling on the internal lower track, of' each. side piece', means on said drawer rolling on said second. set' of rollers, interengaging detent' means, carried by said drawer and by said slidefor causing said slide. to move withsaid. drawer as a unit during, the entire withdrawal oifsaid` slide from. said case, said' last-mentioned means being re,- leased in response to force. appliedtof saiddrawer. at the conclusion of.said` withdrawal. permitting. saiddrawer to be, further witlfldrawn` independently yof said4 slide and. interengaging; detent. means. carried by said. slide and by a. xed part;Y of said case for thereafter maintainingsaidslidey stationary until the application of-4 force; to". saidfA drawer4 after it is again `telescoped` therein.

2. Ina drawer suspension construction, aV case. having side-walls, apair. of` channel-shaped strips. mounted on said` walls with.,tl1e. channels of.y said strips'facing each other,.v each of saidgstrips:pro.-` Viding an upper andar lower internal, track; a slide. including channel-shaped side pieces each. providedfwith an internal: upper trackas wellasa' with` anv internal lower track andfwith: an-exter nal lower track, eachV sidezpiecer nesting withirraA side strip, a roller rotatably mounted-on the rea-r-v portiona ofr each sideipiece 13o/engage ther upper internaly track of itsrelated strip; mea-nszfor limit'-z ing. the. outwarclmovement. offl the-s1ide;, an" emi- :ramener tossing,provided` on the upper internal;- trackof atgleastrfone oisaid: stripsan being located at a.

point thereon at: the; normalY limit. orv outwardmovement` of its cooperating; roller`- to; receive theesame thereimwhereby said slide-v tendsl to be;

frictionally'retained'inlits:outwardzpositionfsetofv spaced rollers.rollingonfthelower track of; each channel i strip: anden` the: external lower track of ai -relatedzsider piecefto affordinwardandoutward travelofi'said slide, adrawerof a sizeto: hey re.-

ceivediwithin said. slide;l a secondset: of spaced.

rollers:rollingjomthe'internalv lower. track of each side=-piece,. flanges .onf the respective sides of said drawer rolling can-.said second, setsiof' rollers, and'. f; am embossing;` provided in:A at least one ofV sa-id flanges and-,beingi located at: a point; thereon at thenor-mall-limit. of. outward movement ofv a; roller ofthe.` related. secondset of rollers; for causing said.. slide toi move with. sa-idr drawer as af. unit permitting; said.r drawerr to be.- further. withdrawnv independently of said slide.v

3. In a drawer suspension construction, acase havingside wa-l1s,a pair of'l channel-shapedstrips mounted on; said walls with" the channels.. of said strips-facing,y eachfot-her each offsaid strips piro-` viding an upper-and a lower internal track, a slide;y including. channel-shaped;V sidepieces'y each providedfwith@ an .internal upper track1as-lwell asA with] annternall lower track andwith an eXter= nal lower track; each. sidepiece. nesting withinv aside -stripggaroller rotatably mountedfonthe rear portion ofl each.- sidepiece tol engage the upper internal track of :its: related. stripa set of spaced rollersA rolling on'the lower: track oi each: channel stripandonr the external lower track of a-relatedv Sider-piece: tov afford. inward' and outward: travel of.' said slide, means for limiting;v the outward movement of4 thesIide;` a drawer 0fl a sizeto be' received within saidtslide; a: second-set of: spaced rollersI rolling, on the internal lowertrack of eachl side piece@ means-1on1. said-` drawer rolling onfy said second set of rollers; cooperating means on apart Iof said drawer andA on aipart of7 saidI slide for causing said-slidet'o movewithsaid draweras al unit duringv the entire withdrawal of' said slide from said case, said cooperating means'including a spring? mount'ed-l onone' ofy said parts toengage theother part andfservingatthe conclusion of saidawithdrawal` tofpermitsaid drawer to befurther withdrawn independently ofsaid4 slide; and

interengaging, frictional means on alpart of*- said slide-and. ona fixed partv of; said case Ifor thereafter `maintainingA;said slide: stationary. until f said drawer is-=again; telescoped therein, saidY fricticnal.` meansincluding a springf mountedion one ofvvsaidV last-mentionedl parts to` engage the: otherpart thereof.

JAMESJR. CLARK. 

